Process of manufacturing building blocks



Patented Oct. 26, 1943 PROCESS OF MANUFACTURING BUILDING BLOCKS Joseph C. Roedig er, Brooklyn, N. Y., assignor to Standard Oil Development Company, a corporation of Delaware No Drawing. Application February e, 1940,

Serial No. 317,521

Claims.

This invention relates to improvements in the methods of treating soils for the manufacture of blocks for use in curtain or hearing wall construction, or'as flooring blocks. These improvements may also be applied to the monolithic laying of soil-asphalt mixtures for low cost roadways, now termed soil stabilization.

'It is well known that dwellings may be made of earth or clay earth which is perhaps the material used in the first buildings erected by man, but the objections to structures of such material were that they often washed away during long, rainy seasons, were susceptible to infestation by rodents, vermin, and the like, and in many cases developed cracks due to stresses set up by climatic changes. Bricks were later used which were prepared by mixing clay and straw and allowing the moulded mixture to harden by exposure to the sun. In the development of brick manufacturing methods, artificial heat was used in order to obtain a stronger material which would resist the efiects of water and thereby be an improvement over the ordinary clay-straw brick.

Building blocks have been manufactured in recent years from a mixture of soil, selected or adjusted to have a satisfactory grading and a suitable content of clay, with the proper amount of cutback asphalt or emulsifled asphalt. This mixture which generally contains water to facilitate the thorough incorporation of the asphaltic material is compacted into blocks of the desired size using known methods of compaction. The finished block is then cured by natural or artificial means so that it may-obtain a suitable strength before use in'construction.

It has been proposed in U. S. application Serial No. 301,777,that was filed October 28, 1939, by Joseph C; Roediger, to prepare building blocks by first mixing powdered asphalt and soil, after which a fluxing agent is added and the mixture shaped into blocks. a

It is an object of this invention to manufacture building blocks using as the major proportion of the material clay or soil which is available mogeneous mixture results; This mixture is thereafter poured into moulds in any desired shape'and subjected to pressure or tamping for compaction whereby an amalgamation of the powdered hard asphalt and the cutback asphalt may result. The proportion of cutback asphalt used may be varied from 1% to 7%, while that of the powdered asphalt may be as low as 1% or 2% and as high as 10%. The relative amount of cutback-hard asphalt is based on: (1) obtaining satisfactory coating; (2) obtaining an asphalt of the desired consistency as a result of the com:

plete fiuxing of the asphalt base in the cutback with the hard asphalt. Powdered hard asphalt having a softening point from 190 F. to 450 F. may be used. A softer asphalt, that is, one having a softening point as low as 90 F., may be used in the cutback asphalt. Suitable wetting agents, such as heavy metal salts of oleic acid, naphthenic acid, sulfonic acid, etc., may be employed.

The heavy metal soaps preferred are lead,

may be compacted by the application of 1388-.

sure or by tamping. The pressure used may be as high as 3000 pounds per square inch, although lower pressures of a few pounds or 50 pounds per square inch may be used. The pr v e of compaction does tend to amalgamate the powdered hard asphalt with the flux oil. However, the major portion of this amalgamation or fluxing may occur on aging or curing with or without first submitting to pressure. The flux oil used-according to this invention is of low viscosity but having an initial boiling point of at least 300 F. Wetting agents, such as lead naphthenate, aluminum sulfonate, etc., may be added to obtain a better dispersion of the fiux oil in the soil. ,1

Another method of treating the soil is by mixing soil with a cutback asphalt until a plastic mixture of the cutback asphalt and the soil is obtained. Powdered hard asphalt -is then incorporated in the plastic mixture to produce higher consistency binder than would be 0 tained from cutbacl casphalt treatment within given period of time. The block is finally formed by pouring the mixture of high consistency plastic .mlxture and the mixin continued until a homixture and hard powdered asphalt intomoulds and compacting by the application of pressure or by tamping. Wetting agents, such as lead naphthenate. aluminum sulfonate, etc., may be added to the soil together with the cutback asphalt in order to obtain a better dispersion of the cutback asphalt in the soil.

I claim: l. A process of manufacturing building blocks,

' curtain wall blocks and floor blocks which comprises, mixing a soil with an emulsified cutback asphalt to obtain a thick plastic. mass in which the said asphalt used has a softening point of at least 97 F., adding a powdered hard asphalt having a softening point from 190 to 450 F. to the plastic mass, molding into shape, and subjecting to pressure.

curtain wall blocks and floor blocks which comprises, mixing a soil with an emulsified cutback asphalt to obtain a thick plastic mass in which the said asphalt has a softening point of at least 97 F., adding a powdered hard asphalt having a softening point from 190 to 450 F. to the plastic mass, adding a heavy metal soap, molding the mixture into shape and subjecting to ressure.

3. A process according to claim 2 in which the heavy metal soap is lead naphthenate.

4. A process according to claim 2 in which the heavy metal soap is lead oleate.

5. A process-according to claim 2 in which 15 the heavy 'metal soapis lead sulfonate. 2. A process of manufacturing building blocks, 7

JOSEPH C. ROEDIGER. 

